Have you read what RecieveNotify does?
code:
'//////////////////////////////////////////////////////////////////////
'// //
'// Purpose: Allow special actions when a plugin text is received //
'// //
'// Definition: //
'// This function is called everytime Messenger Plus! detects a //
'// plugin text ID in a message received from a user. This ID is //
'// generally placed at the beginning of a text by a plugin //
'// command to perform an action on the destination computers. //
'// This can be used, for example, to play a sound. See the //
'// control characters section for more information. //
'// //
'// Parameters: //
'// * sNotifyCode: this 5 character string is the notify code that //
'// was sent next to the plugin ID control character. Use it to //
'// identify what action to perform. //
'// * sText: the rest of the received message. You can use it to //
'// get more information about the action you want to perform. //
'// However, you MUST NOT use this parameter to determine if an //
'// action is supported by your plugin. Use sNotifyCode instead. //
'// * sContactName: friendly name of the contact who sent this //
'// text. //
'// * oConversationWnd: Messenger Conversation Window COM //
'// interface. The type of this object is //
'// "MessengerConversationWnd". For more information, consult //
'// the public Messenger API documentation on Microsoft's web //
'// site. //
'// * sTextToSend: this parameter is optional. You can use it if //
'// you want to ask Messenger Plus! to send a new message after //
'// this one has been displayed. This WON'T modify the message //
'// associated with the notify code, this will simply send a new //
'// one. //
'// * return value: if you recognized the notify code return True, //
'// else, return False. //
'// //
'// Advanced: if the plugin version returned by Initialize() is 2 or //
'// above, you can specify more than one message or command in //
'// sTextToSend. Simply create new lines with # as first character //
'// (use vbLf to create new lines in your string). Up to 20 actions //
'// can be specified, each being executed at a 0.5 second interval. //
'// A different delay can even be entered for each action. After the //
'// first #, just put a digit between 1 and 9 and another #. //
'// Example: sTextToSend = "#First message\n#5#Second message" //
'// //
'// Important: keep in mind that several plugins can be installed //
'// and that a lot of text is received. If you don't support the //
'// notify code passed in parameter, you must return as fast as //
'// possible and without doing anything else. //
'// //
'//////////////////////////////////////////////////////////////////////
Read that and let me know if you have any questions.